Portable kiln



July 20, 1965 s. WEINGRAD 3,196,252

PORTABLE KILN Filed March 7, 1963 2 Sheets-Shet 1 47 INVENTOR. 48

49 Saul Wemgrad ATTORNEY July 20, 1965 S. WEINGRAD PORTABLE KILN FiledMarch 7, 1963 Sheets-Sheet 2 INVENTOR.

Saul Weingrad Y WM ATTORNEY United States Patent ice 3,196,252 PORTABLEKILN Saul Weingrad, 129 Stony Ridge Drive, Hillsdale, NJ.

Filed Mar. 7, 1963, Ser. No. 263,447 a 2 (Ilaims. '(Cl. 219-394) Thisinvention relates in general to a portable kiln, and more specificallyto an improved portable kiln which is readily adapted for hobby, test orlaboratory use and which is versatile in operation for efiiciently andeconomically firing either a capacity load or less than a capacity loadof ware, and/or for simultaneously firing pieces of ware at differenttemperatures and/or in different time cycles.

Heretofore, the small kilns used by hobbyists, schools, manufacturers,test laboratories and the like, had many undesirable limitations imposedthereon. As a technical matter it is not desirable to fire a kiln unlessthe inside cubic area of the kiln is filled to capacity with ware. Thisis'necessary in order to obtain uniform distribution and transfer of theheat to the ware for obtaining optimum firing results. Because the cubicarea or volume of the kiln, heretofore known, was fixed for a givencapacity load, it frequently happened that when only one piece of ware,or ware of less than full capacity was fired, the heat, instead of beingreflected into the ware, was absorbed by the walls of the kiln. Warethat is fired in too large a volume does not get the desired uniformfiring. Ther'efore, for optimum results, the kiln must be completelyfilled with ware so that the heat maybe absorbed primarily by the ware.Consequently, the disadvantage of the prior known kiln constructions wasthat for less than capacity loading, the firing of the ware wasinefficient and uneconomical. For this reason firing was generallydelayed until a full capacity was readied. Oftentimes, in specific testsor hobby applications, a full load was never possible. Also itfrequently happens that a piece of ware may be larger than the availablevolume of a kiln which is sized to fire but small pieces. Thus, theversatility of the known kiln constructions was greatly limited.

For the foregoing reasons, much difiiculty has been encountered by thoseworking on relatively small specialized projects or tests that requirethe use of a kiln. There also arise situations in which several piecesof ware, which could otherwise be fitted into a given volume of a kiln,which required for various reasons to be fired at a differenttemperature or in a different timing cycle. Because the prior known kilnconstructions could not readily handle such mixed firing situations, theceramist was forced to fire either all the ware in the same manner, orelse he was required to make two or more runs in which the specificpieces of ware are fired in accordance with the manner desired.

Therefore, an object of this invention is to provide a new and improvedportable kiln construction which is arranged and constructed so as torender it more versatile than the portable kiln heretofore known.

Another object of this invention is to provide a portable kilnconstruction in which the capacity or volume of the kiln to be fired canbe varied at will and with a minimum of effort so as to accommodatedifferent loads of ware, yet permitting the kiln to be fired at optimumfull load capacity.

Still another object of this invention is to provide a kiln constructionin which pieces of ware may be simultaneously fired at varyingtemperatures and/or timing cycles.

Still another object of this invention is to provide a single unitarykiln which is constructed and arranged so as to be readily divided intotwo or more heating compartments so as to accommodate a full capacityload or load less than capacity under firing conditions which areoptimum for full load, firing.

Another object of this invention is to provide a readily portableversatile kiln which is relatively inexpensive to construct, which iseasily fabricated, and which is posi= tive in operation. A I

Still another object of this invention is to provide a kiln having areadily removable divider for optionally divid ing the heating chamberof the kiln into a plurality of compartments and which divider isconstructed and arranged so as to thermally insulate one compartmentfrom another. c q I In accordance with this invention the foregoingobjects, and other features andadva'ntages are attained by a p'ort ablekiln comprising essentially a housing lined with re fractory material todefine a heating chamber which can be Op'tionallydivide'd into aplurality of firingcompartments by means of a readily removable dividermeans. In accordance with this invention the divider means isspecifically arranged and constructed so as to thermally insulate onefiring compartment from the other when the divider meansis disposedwithin the heating chamber and still provide a strong support forcarrying the ware. If desired, a heating elementmay be embedded in theexterior surface of the divider means so as to supplement the heatingelements which line the enclosing walls of the heating chamber in therespective compartment areas.

' Inaccordanc'e with'this invention the heating chamber and therespective compartments partitioned therefrom may be constructed so asto be loaded from either the top or front. In either event the heatingchamber is sealed by closure means which are pivotally mounted to. thehousing for swinging between open and closed positions. The constructionof the closure means is such that it comprises a plurality of separateand distinct door means which are constructed and arranged so as tocover the access opening to each of the respective compartments definedby the divider means of the heating chamber. The arrangement oftherespective door means is such that any one may be operated independentlyof the other, or all of the doors may be opened as one. The latterpossibility is attained by suitable means for latching the doorstogether whereby the respective doors may be opened simultaneously.Several heating means line the walls of the respective compartments andmeans are provided for independently controlling the actuation of therespective heating means.

Therefore, a feature of this invention resides in a use of a novellyconstructed divider means for partitioning the heating chamber into aplurality of separate and distinctv compartments, the arrangement beingsuch that for small load firings only one of the chambers is madeavailable to the exclusion of the other so as to obtain optimum firingconditions for less than capacity loads.

Other featuresand advantages will become more read: ily apparentwhen-consideredin view of the specification and drawings in which: 1

FIG. 1 is a perspective view of the'improved front loading portable kilnconstruction in accordance with this invention; I

. FIG. 2 is a front perspective view of the portable kiln constructionof FIG. 1 illustrated with the doors thereof in the open position;

FIG. 3 illustrates a perspective view of the kiln of FIG. 1 in whichonly one of the doors is open; I

FIG. 4 is a detailed perspective view of the improved dividerconstruction which partitions the heating chamber of the kiln of FIG. 1into two separate and distinct compartrnentsg FIG. 5 illustrates a topplan view of a slightly modified kiln construction; and

Patented Ju ly ZO, 1965' FIG. 6 illustrates a modified divider means foruse in the kiln of FIG. 5.

Referring to the drawings, there is illustrated therein the improvedkiln construction of this invention. As shown in FIGS. 1 to 4, the kilnconstruction 19 comprises a housing 11 which is defined by a top wall12, a bottom wall 13, a pair of opposed side walls 14, 15, and a rearwall 16 for defining therein a heating chamber 17. The interior walls ofthe housing 11 are lined with suitable heat resistant refractorymaterial. In accordance with this invention the respective side walls14, 15 and rear wall 16 are provided with a groove or recess 18 which isdisposed in the horizontal plane intermediate the height of therespective side walls 14, 15 for slidably receiving therein a dividermeans 19 which is arranged to divide the heating chamber 17 into twoseparate and distinct compartments 17A, 178. While only one dividermeans 19 is shown, it will be understood that more than one may beprovided if it is desired to partition the heating chamber 17 into morethan two compartments.

In accordance with this invention the partition or divider means 19comprises a hollowed block of refractory material. In physicaldimensions this block comprises a refractory block approximately fiveinches thick in which the walls 19A, 19B of the block are approximatelyone inch thick to define a hollow chamber 20 approximately three inchesthick. In accordance with this invention the hollow of the refractoryblock is filled with an insulating material 21. A suitable material forobtaining the desired results is aluminum silicate fiber which is tradedunder the trademark of Fibrefrax. Thus with the divider construction 19defined, it has been found that the maximum amount of thermal insulationis afforded with a minimum of thickness.

As illustrated in FIG. 3, it will be noted that one surface of theheating block is provided with a groove 22 which is adapted toaccommodate a heating element 23, as for example, an electricalresistant heater. In the illustrated embodiment, the arrangement is suchthat when the block 19 is disposed within the heating chamber 17 todivide it into the two distinct compartments, the heater 23 in the blockor divider can be utilized to supplement the heating of the adjacentcompartment defined thereby.

As shown in FIG. 2, each of the respective compartments 17A, 17B definedby the divider block 19 has provided in the side and rear walls thereofrecessed areas 24 for accommodating the independent electrical heaters25, 26 and 27, 28 which are utilized to heat each of the compartmentsrespectively. In accordance with this invention the controls for therespective heaters 25, 26 and 27, 28 are located on the side 15 of thehousing as best seen in FIG. 1.

In the illustrated embodiment of FIGS. 1 to 4, it will be noted thatthree heaters are used to heat the respective compartments. Heaters 25and 26, which line the wall portions of the upper compartment, andheater 29 which is located on the door of the upper compartment, as willbe hereinafter described, can be used to heat the upper chamber 17A.Also heater 23 in the divider 19 can supplement heaters 25, 26 and 29 toheat the upper chamber 17A. Heaters 27 and 28 which lined the walls ofthe lower compartment 178 and heater which lines the face of the doorclosing the lower compartment 17B, as will be hereinafter described areutilized to heat the lower chamber.

As shown in FIG. 4, each of the heaters 23, 25, 26, 27, 28, 29, 30 isprovided with a corresponding switch 23A, 25A, 26A, 27A, 28A, 29A and30A so that each of the heaters may be independently controlled. Todetermine which of the heater elements are energized, an indicatinglight 23B, 25B, 26B, 27B, 28B, 29B, and 30B is connected into therespective heater circuit, in a manner well known to those skilled inthe art.

In accordance with this arrangement a closure means 31 is provided forclosing the access opening to the heating chamber. In the illustratedembodiment it will be noted that the closure 31 comprises a plurality ofseparate and distinct doors, 31A, 313 one for each compartment. Each ofthe doors 31A, 31B is hingedly connected to the housing about a verticalaxis or hinge pin 32. Each door is also lined with a suitable refractorymaterial. As shown in FIG. 2 the door 31A, 31B is provided with astepped portion 33, 34 respectively in which the respective heatingelement 29, 30 is embedded. The arrangement is such that the lower edgesof the door are disposed in contiguous or abutting relationship, andmeans are provided for latching the respective doors together so thatthey may be utilized either as separate and independently operateddoors, or as a unitary closure when the divider means is not utilized.Means for latching and unlatching the respective doors 31A, 318 to oneanother so that they may be either opened independently of one anotheror simultaneously all together, comprising a latch 35 which is pivotallymounted to the lower door 31B, and an L- shaped catch 36 fixed to theupper door 31A. The arrangement is such that to connect the doors 31A,31B so that they open simultaneously, the latch 35 need be merelyrotated to engage the catch 36 of the upper door. Thus it will beapparent, when viewing FIG. 1, that a pull on either of the door handles37, 38 will effect opening of the doors 31A, 31B simultaneously. In theevent that only a portion or one compartment of the heating chamber 17is being fired, as for example, when the divider block is in place, thedoor of the firing compartment can be opened independently of the otherdoor merely by pivoting the latch 35 in a clockwise direction, as viewedin FIG. 1 to effect its disengagement from the catch 36. Thus as seen inFIG. 4, either one or the other door may be independently opened withoutinterfering with the other.

From the arrangement described it will be readily apparent that the kilnconstruction 10 described may be readily adapted for use for either fullload firing, or for less than full load firing. For example, when it isdesired to fire the kiln 10 at full capacity the divider unit 19 issimply removed, and the ware positioned within the heating chamber 17 soas to occupy the entire volume thereof. The doors, which are latchedtogether are then closed as a unit, and the desired heating elementsenergized by the closing of the appropriate switches controlling thesame.

In the event that less than the capacity load is to be fired, i.e. anamount of were not capable of occupying the volume of chamber 17, theceramist need only to insert the partition member 19 and utilize eitherone or the other of the smaller compartments 17A, or 173 definedthereby. Therefore, for less than capacity firing, the ware required toobtain the desired optimum firing conditions need only be half or someother proportion or fraction thereof of that otherwise required to fillthe full heating chamber. Therefore, the advantage obtained by theinstant invention is that a less than capacity load of ware can be firedin one or the other chamber, and the subsequent firing resultingtherefrom will then have all the advantages that full load firing wouldotherwise attain.

Also it will be readily apparent that without the divider unit 19, largepieces of ware, or full capacity loading of ware can be economicallyfired at optimum firing conditions. Also that by utilizing the divider19 in the heating chamber 17, one or the other of the compartments 17A,1713 can be fired with less than capacity loading while attaining theoptimum firing conditions of full capacity firing.

With the construction defined it will be further readily apparent thatwhen the divider is in place, one compartment 17A or 17B of the heatingchamber 17 may be used to accommodate a particular type of glaze ordecorating firing operation while at the same time the other compartmentmay be used for firing at a different temperature and/or time cycle.

It is to be further noted that the divider unit 19 is made of arefractory material in a particular manner so as to produce maximuminsulation in the minimum amount of area, and that if a supplementalheating element is required, it can be constructed into the dividerelement 19, as shown in FIG. 3. Therefore, from the foregoingdescription it will be readily apparent that the construction definedresults in a more versatile kiln than was heretofore known.

FIGS. 5 and 6 illustrate a slightly modified construction. As shown inFIG. 5, the kiln 40 is constructed so that it can be loaded from thetop. Structurally it is similar to that of the kiln of FIGS. 1 to 4 withthe exception of having a top opening closure 41, and a slightlymodified divider construction 42.

Essentially, the housing 43 of kiln 40 is made up of a front wall 44,rear wall 45, side walls 46, 47 and bottom wall 48 to define a heatingchamber 49 which can readily be divided into two or more compartments49A, 49B by removable divider means 42. In FIG. 5, the kiln 40 is shownas being divided into two compartments. However, by employing otherdividers 42, the number of compartments can be varied.

In this form of the invention of FIGS. 5 and 6, the divider 42 isconstructed so a heater 42A, 42B is built into each side thereof. Thus,when the divider 42 is installed, the respective heaters 42A, 4213 canbe used to supplement the heater of the respective compartments 49A, 49Bdefined thereby.

The closure means 41 is similar to that hereinbefore described, exceptthat it pivots about a horizontal axis so as to facilitate top loadingof the respective compartments. In all other respects, the kiln of FIGS.1 to 4 and the kiln 40 of FIGS. 5 and 6 are substantially similar.

While the instant invention has been disclosed with reference to aparticular embodiment thereof, it is to be appreciated that theinvention is not to be taken as limited to all of the details thereof asmodifications and variations thereof may be made without departing fromthe spirit and scope of the invention.

What is claimed is:

1. A versatile portable kiln readily adaptable for firing simultaneouslya plurality of ware pieces either at the same temperature or atdifferent temperatures comprising (a) a refractory lined housing havinga front wall, a

bottom wall, a rear wall, and opposed interconnecting side walls fordefining a heating chamber having a full open top access opening,

(b) said opposed front and rear walls having a coplanar groove formed inthe inner surface thereof intermediate the ends thereof,

(c) a readily removable divider means slidably received in said groovesfor dividing said chamber with two distinct top loading compartments,

(d) said divider means including a hollow refractory block,

(e) a high heat resistant material packed in the hollow of said dividerblock to thermally insulate one compartment from the other when saiddivider is in place,

(f) an electric heating element embedded in each surface of said dividerblock,

(g) a plurality of electric heating elements lining the side, front andrear wall portions of the respective compartments, 7 1

(h) means for independently controlling the operation of the respectiveheating elements,

(i) and a closure means for sealing the access opening to said chamber,

(3') said closure means including a pair of doors hingedly connected tosaid housing,

(k) each of said doors defining a closure for each of said compartments,

(1) means for independently operating the opening and closing of saiddoors,

(m) and means for latching said doors together to effect simultaneousopening and closing of said doors.

2. A versatile portable kiln readily adaptable for simultaneously firinga plurality of ware pieces either at the same temperature or atdifferent temperatures comprising (a) a refractory lined housing havinga top wall, bottom wall, rear wall, and opposed interconnecting sidewalls for defining a heating chamber havinga full open front accessopening,

(b) said opposed side walls and rear wall having a horizontally disposedco-planar groove formed in the inner surfaces thereof intermediate theheight thereof,

(c) a readily removable divider means for dividing said chamber with twodistinct compartments slidably received in said groove,

(d) said divider means including a hollow refractory block,

(e) a high heat resistant aluminum silicate fiber material packed in thehollow of said divider block to thermally insulate one compartment fromthe other when the divider is in place,

(f) an electric heating element embedded in each surface of said dividerblock,

(g) a plurality of electric heating elements lining the side and rearwall portions of the respective compartments,

(h) means for independently controlling the operation of the respectiveheating elements,

(i) and a closure means for sealing the access opening to said chamber,

(j) said closure means including a pair of doors hingedly connected tosaid housing,

(k) each of said doors defining a closure for each of said compartments,

(I) handle means for independently operating the opening and closing ofsaid doors,

(m) and latching means for latching said doors together for effectingthe simultaneous opening and closing of said doors.

References Cited by the Examiner UNITED STATES PATENTS RICHARD M. WOOD,Primary Examiner.

2. A VERSATILE PORTABLE KILN READILY ADAPTEABLE FOR SIMULTANEOUSLYFIRING A PLURALITY OF WARE PIECES EITHER AT THE SAME TEMPERATURE OR ATDIFFERENT TEMPERATURES COMPRISING (A) A REFRACTORY LINED HOUSING HAVINGA TOP WALL, BOTTOM WALL, REAR WALL, AND OPPOSED INTERCONNECTING SIDEWALLS FOR DEFINING A HEATING CHAMBER HAVING A FULL OPEN FRONT ACCESSOPENING, (B) SAID OPPOSED SIDE WALLS AND REAR WALL HAVING A HORIZONTALLYDISPOSED CO-PLANAR GROOVE FORMED IN THE INNER SURFACES THEREOFINTERMEDIATE THE HEIGHT THEREOF, (C) A READILY REMOVABLE DIIDER MEANSFOR DIVIDING SAID CHAMBER WITH TWO DISTINCT COMPARTMENTS SLIDABLYRECEIVED IN SAID GROOVE, (D) SAID DIVIDER MEANS INCLUDING A HOLLOWREFRACTORY BLOCK, (E) A HIGH HEAT RESISTANT ALUMINUM SILICATE FIBERMATETERIAL PACKED IN THE HOLLOW OF SAID DIVIDER BLOCK TO THERMALLYINSULATE ONE COMPARTMENT FROM THE OTHER WHEN THE DIVIDER IS IN PLACE,